Pump

ABSTRACT

A pump for conveying a fluid comprises a pump housing ( 1 ) with a fluid inlet ( 26 ), a pumping chamber ( 4 ), which has a flow connection to the fluid inlet ( 26 ), and a fluid outlet ( 25 ), which has a flow connection to the pumping chamber ( 4 ). The pump furthermore has a drivable pump body ( 2 ), which at least partially limits the pumping chamber ( 4 ), and a pump body drive device. The pump body drive device comprises a pump body drive mechanism ( 3 ) which is connected to the pump body ( 2 ) and which comprises a first drive magnet ( 16 ) and is moveable along a displacement path, and a second drive magnet ( 11 ) arranged adjacent to the pump body drive mechanism ( 3 ) for moving the pump body drive mechanism ( 3 ) along the displacement path. The pump also comprises an actuable fixing device ( 33 ) for fixing the pump body drive mechanism ( 3 ), which, in a release position, releases the pump body drive mechanism ( 3 ) and, in a fixing position, fixes the pump body drive mechanism ( 3 ).

The invention relates to a pump, in particular a diaphragm pump, forconveying a fluid. The fluid to be conveyed is taken to mean a medium tobe conveyed, such as a liquid, a gas, a gas mixture or a liquid/gasmixture. The pump is preferably used in continuous operation in smallsewage plants. Small sewage plants of this type are often used to purifywaste water in buildings which do not have their own sewage systemconnection. The pump is preferably used to introduce air into the wastewater. The waste water is thus enriched with oxygen. Bacteria are thusactivated for the biological or bacterial purification of the wastewater. The pump is therefore preferably an aeration pump.

A large number of pumps are known from the prior art and are used insmall sewage plants, for example. The disadvantage in these known pumpsis that their wearing parts—such as their diaphragm—often have to beexchanged after a few years. The exchange of the wearing parts isrelatively time-consuming Technical skill is generally necessary toexchange the wearing parts.

The invention is therefore based on the object of providing a pump, thewearing parts of which can be exchanged particularly easily and quickly.

This object is achieved according to the invention by the featuresdisclosed in claim 1. The core of the invention is that the at least onepump body drive mechanism can be locally fixed by the at least onefixing device. In particular, this prevents the fixed pump body drivemechanism being able to unintentionally move or be moved duringmaintenance work. A simple exchange of a pump body is thus possible, forexample,

For example, during maintenance work, it can thus also be prevented thata pump body drive mechanism comprising at least one drive magnet isattracted by at least one stationary drive magnet and is fixed thereto.The release of the magnets is generally very difficult. A pump bodydrive mechanism of this type preferably has at least a first drivemagnet. It is advantageous if the at least one pump body drive devicefurthermore has at least one second drive magnet arranged adjacent tothe at least one pump body drive mechanism to move the at least one pumpbody drive mechanism along the displacement path. Another configurationof the pump body drive device is alternatively possible.

The at least one pump body may, for example, be configured as adiaphragm. However, it may also be a piston. Two pump bodies arepreferably provided. It is also advantageous if two fixing devices areprovided. These can preferably be actuated independently of one another.The fixing devices may, however, also be coupled to one another forcommon actuation.

Further advantageous configurations are disclosed in the sub-claims.

The configuration according to claim 2 allow simple actuation orhandling of the fixing device. An actuating device is preferablyprovided for each fixing device. However, two fixing devices may also beactuated by one actuating device. The actuating device may bedisplaceably or pivotably mounted on the pump housing. It preferablycomprises at least one actuating means. Examples of possible actuatingmeans are an actuating handle or a handle trough. The actuating meansmay, however, have been produced by knurling. The actuating device maybe mounted on the inside or outside of the pump housing. With insidemounting of the actuating device, the actuating means is preferablyconfigured as an actuating handle or lever, which can then project fromthe pump housing through a recess formed in the pump housing.

The configuration according to claim 3 leads to an extremelyfunctionally reliable fixing of the pump body drive mechanism. Thefixing part may engage, preferably positively, in the pump body drivemechanism. The pump body drive mechanism then preferably has at leastone corresponding recess or opening for this. The fixing part may,however, also rest on the outside of the pump body drive mechanism. Itmay rest thereon laterally or on the end face. The fixing part may,however, also partially encompass the pump body drive mechanism in aclamp-like manner Each fixing device preferably has one or two fixingparts.

The configuration according to claim 4, in a functionally reliablemanner, prevents a further displacement of the pump body drive mechanismalong its displacement path. The pump body drive mechanism may also befixed, however, alternatively or additionally, transverse to itsdisplacement path. The at least one fixing part is preferably configuredin such a way that, in its fixing position, it fixes the pump body drivemechanism in the direction of its displacement path and preferably alsotransverse to its displacement path. The fixings acting in differentdirections can be achieved by common fixing parts or by fixing partswhich are separate from one another.

The configuration according to claim 5 allows an extremely preciseplacing of the pump body drive mechanism. It can thus be guidedprecisely to its desired fixing position.

The configurations according to claims 6 and 7 lead to an extremelyprecise placing of the pump body drive mechanism.

The configuration according to claim 8 results in an extremely highfunctional reliability. Moreover, a pump of this type is extremely easyto handle during maintenance.

The configuration according to claim 9 produces an extremelyfunctionally reliable fixing device. The coupling wedge and the fixingpart configured in the manner of a wedge have a sliding connection withone another by means of their wedge faces. An actuation of the couplingwedge leads to a movement of the fixing part, whereby a movementdeflection takes place. Two wedge mechanisms per fixing device arepreferably provided. Each fixing device preferably also has two fixingparts, it being possible for a spring element to be provided betweenthese fixing parts for the movement thereof into their release position.The spring element may be configured as a leaf spring, helical spring,elastomer spring or as a spring block. Instead of spring elements,corresponding guides may also be provided, which bring about a return ofthe fixing parts. A swallowtail guide may, for example, be used forthis. The fixing parts, in the fixing position, preferably restlaterally on the pump body drive mechanism.

The configuration according to claim 10 also leads to an extremelyreliable fixing of the pump body drive mechanism. The encompassing body,in the fixing position, preferably encompasses the pump body drivemechanism in the region of its longitudinal sides. A positive connectionis preferably present between the encompassing body and the pump bodydrive mechanism.

The configuration according to claim 11 leads to an easy andfunctionally reliable actuation of the fixing part. The link ispreferably configured in or on the actuating device, while the link pinis connected to the fixing part. According to an alternative embodiment,the link is configured on the fixing part, while the link pin isprovided on the actuating device.

The configuration according to claim 12 is particularly operationallyreliable.

The configuration according to claim 13 has an extremely simplestructure. The link is then preferably configured as a link cam orcontrol cam. A spring element, which brings the fixing part into contactwith the link cam, is preferably associated with each fixing part.

The configuration according to claim 14 is again extremely simple withregard to structure. It is also extremely assembly-friendly andfunctionally reliable.

The configuration according to claim 15 leads to an extremely highoperating reliability.

Four embodiments of the invention will be described below by way ofexample with reference to the accompanying drawings, in which:

FIG. 1 shows a perspective view of a pump according to the invention inaccordance with a first embodiment,

FIG. 2 shows a section through the pump shown in FIG. 1,

FIG. 3 shows an exploded view of the pump shown in FIGS. 1 and 2,

FIG. 4 shows a view which shows the actuating device or fixing device ofthe pump shown in FIGS. 1 to 3,

FIG. 5 shows a section along the section line V-V shown in FIG. 4,

FIGS. 6 and 7 show sections through the pump shown in FIGS. 1 to 3, thepump body drive mechanism being released.

FIG. 8 shows a view of the pump shown in FIGS. 1 to 3, the fixing devicebeing located in its centring position,

FIG. 9 shows a section along the section line IX-IX in FIG. 8,

FIGS. 10 and 11 show sections through the pump shown in FIGS. 1 to 3,the fixing device being located in its fixing position,

FIG. 12 shows a perspective view of a pump according to the invention,in accordance with a second embodiment,

FIG. 13 shows an exploded view of the pump shown in FIG. 12,

FIG. 14 shows a perspective view of the fixing devices, the actuatingdevices and the pump body drive mechanism of the pump shown in FIGS. 12and 13,

FIG. 15 shows a perspective view of the actuating device of the pumpshown in FIGS. 12 and 13,

FIG. 16 shows a view of the pump shown in FIGS. 12 and 13, the fixingdevice being in its release position,

FIGS. 17 and 18 show sections through the pump shown in FIGS. 12 and 13,the fixing device being in a centring position,

FIG. 19 shows a section through the pump shown in FIGS. 12 and 13, thefixing device being in its fixing position,

FIG. 20 shows a perspective view of a pump according to the invention inaccordance with a third embodiment,

FIG. 21 shows a section through the pump shown in FIG. 20,

FIG. 22 shows a further section through the pump shown in FIG. 20, thepump body drive mechanism being released,

FIG. 23 shows a perspective view of the actuating device of the pumpshown in FIGS. 20 to 22,

FIG. 24 shows a perspective view of the fixing devices and the actuatingdevice of the pump shown in FIGS. 20 to 22,

FIG. 25 shows a section corresponding to FIG. 22, the fixing devicesbeing in their fixing position,

FIG. 26 shows a perspective view of a pump according to the invention inaccordance with a fourth embodiment,

FIGS. 27 and 28 show sections through the pump shown in FIG. 26, thepump body drive mechanism being released,

FIG. 29 shows a perspective view of the fixing devices shown in FIGS. 26to 28, the actuating devices and the pump body drive mechanism,

FIG. 30 shows a section through the fixing devices, the actuatingdevices and the pump body drive mechanism of the pump shown in FIG. 26,the pump body drive mechanism being released,

FIG. 31 shows a section corresponding to FIG. 30, the fixing devicesbeing in their centring position, and

FIG. 32 shows a section corresponding to FIGS. 30 and 31, the fixingdevices being in their fixing position.

A first embodiment of the invention will be described below withreference to FIGS. 1 to 11. A pump according to the first embodimentcomprises a pump housing 1, diaphragms 2 and a diaphragm drive mechanism3 for actuating the diaphragms 2. The diaphragms 2 and the diaphragmdrive mechanism 3 are housed in the pump housing 1. The diaphragms 2 andthe pump housing 1 together limit pumping chambers 4, which can bechanged with regard to their volume. The diaphragms 2 are flexible andimpermeable to fluid. By actuating the diaphragms 2 by the diaphragmdrive mechanism 3, a fluid is conveyed by changing the volume of thepumping chambers 4. The diaphragms 2 form pump bodies, while thediaphragm drive mechanism 3 is a pump body drive mechanism.

The pump housing 1 comprises a panel 5, which is U-shaped in design. Thepanel 5 therefore has a U-base 6 and two U-legs 7 projectingperpendicularly from the U-base 6. The open sides of the panel 5 are ineach case closed when the pump is assembled. Opposing the U-base 6, afirst panel cover (not shown) is provided for this. Furthermore, twosecond panel covers (not shown) are provided, which then oppose oneanother and rest laterally on the U-base 6 and the U-legs 7. The panelcovers are preferably screwed to the panel 5 by screws. They togetherform a U-shape, the first panel cover forming the U-base. The U-base 6,the U-legs 7 and the panel covers are plate-shaped in each case. Theytogether limit a cuboid receiving space 8 and together form the pumphousing 1.

Provided in the receiving space 8 are two yokes 9, which are arrangedspaced apart from one another and are preferably formed from an ironmaterial. The yokes 9 are fastened to the panel 5. They are preferablyfixed to the U-base 6. Each yoke 9 is E-shaped and therefore has acentral, finger-like projection 10. Wound around each projection 10 is acoil 11, by which electrical current can be carried. The projections 10in each case form a core for the coils 11 and run toward one another.The yokes 9 and the coils 11 form electric drive magnets 12.

Arranged between the yokes 9 and the associated coils 11 is thediaphragm drive mechanism 3, which is configured as an armature, shuttleor the like. The armature 3 is moveable and plate-like. It has arectangular, elongate shape and therefore a longitudinal centre axis 13.The armature 3 can be axially displaced along its longitudinal centreaxis 13. It comprises a frame 14 with two window-like openings 15, whichare arranged next to one another in the direction of the longitudinalcentre axis 13. A permanent magnet 16 is inserted in each opening 15.Opposite poles of the permanent magnets 16 are arranged next to oneanother.

The permanent magnets 16 of the armature 3 are located in a magneticfield, which is produced by the electric drive magnets 12 when the coils11 are provided with current. By providing the coils 11 with current,the armature 3 is moved axially between the yokes 9. The armature 3 thenoscillates along its longitudinal centre axis 13. It moves, in thiscase, alternately in the direction of the mutually opposing U-legs 7.

The diaphragms 2 are fastened to the mutually opposing longitudinal endsof the armature 3. The centres of the diaphragms 2 are in this casefixed to the armature 3. For this purpose, compression discs may beprovided on the armature 3 and rest on the inside of the diaphragms 2.On the outside, fixing discs rest on the diaphragms 2 and are screwed tothe associated compression discs.

Configured in each U-leg 7 is an opening 17 which completely passesthrough the U-leg 7. The openings 17 are circular and oppose oneanother. Their centre point is located on the longitudinal centre axis13 of the armature 3 when the pump is assembled.

A pump head 18, which is a component of the pump housing 1, isassociated with each opening 17. Each pump head 18 comprises a chamberpart 19, which is configured in a shell-like manner and is held byscrews on the outside on the respective U-leg 7. The pump heads 18, whenthe pump is assembled, oppose one another. The chamber part 19 in turnhas a diaphragm clamping region 20, which runs round the respectiveopening 17 and rests closely on the outside of the respective U-leg 7.Furthermore, each chamber part 19 has a valve receiving region 21, whichis arranged spaced apart from the respective U-leg 7 with the formationof the respective pumping chamber 4. Each chamber part 19 furthermorehas a peripheral wall 22, which connects the diaphragm clamping region20 and the valve receiving region 21 to one another. The chamber part 19tapers from the diaphragm clamping region 20 in the direction of thevalve receiving region 21.

A pressure valve receiver 23 and a suction valve receiver 24 are formedin each valve receiving region 21. The pressure valve receiver 23 isarranged adjacent to a pressure opening 23, while the suction valvereceiver 24 is placed adjacent to a suction opening 26. The pressureopening 25 and the suction opening 26 are in each case arranged in thevalve receiving region 21 and pass through it completely.

Furthermore, each pump head 18 comprises a valve cover 27, which isplaced tightly onto the outside of the respective chamber part 19 andadjoins the valve receiving region 21. The valve cover 27 is screwed tothe respective chamber part 19. In this case, the valve cover 27 holds asuction valve plate 28 in the suction valve receiver 24. The suctionvalve plate 28 can close the suction opening 26. Moreover, the valvecover 27 holds a pressure valve plate 29 in the pressure valve receiver23. The pressure valve plate 29 can close the pressure opening 25. Thevalve plates 28, 29 can be moved between a closing position, in whichthe opening 26 or 25 is released. They are pressure-controlled. Eachvalve cover 27 moreover has a pressure line 30 and a suction line 31.The pressure lines 30 have a flow connection with the pressure openings25, while the suction lines 31 have a flow connection to the suctionopenings 26.

The pump furthermore comprises two actuating devices 32. Each actuatingdevice 32 is non-rotatably connected to a fixing device 33. Theactuating devices 32 and the associated fixing devices 33 are in eachcase preferably configured in one piece. They form actuating/fixingunits. The actuating/fixing units are cylinder-like in design. They eachhave a centre axis 34. The actuating/fixing units oppose one anotherwhen the pump is assembled.

Each actuating device 32 comprises an annular contact web 35 and anactuating handle 36 projecting radially from the contact web 35. Thecontact webs 35 in each case have an outer face 37 and an inner face 38opposing the outer face 37. The external diameter of the contact webs 35is larger than the diameter of the openings 17. When the pump isassembled, the inner faces 38 rest adjacent to the openings 17 on theU-legs 7 on the outside. The inner faces 38 of the actuating devices 32face one another here. The diaphragms 2 rest on the outer faces 37 ofthe actuating devices 32. They are held there by the chamber parts 19,which are screwed to the pump housing 1 or to the respective U-leg 7.

Alternatively, the contact webs 35 may rest on the U-legs 7 on theinside.

Each fixing device 33 comprises a base body 39, which adjoins the innerface 38 of the respective contact web 35. The base bodies 39 in eachcase have an external diameter, which is slightly smaller than thediameter of the openings 17. When the pump is assembled, the base bodies39 project through the openings 17 into the receiving space 8 and reston the limit wall 40 which limits the respective opening 17 and thenforms a bearing face.

Each base body 39 is point-symmetrical with respect to its centre ofsymmetry and has an elongate, rectangular, window-like opening 41, whichcompletely axially passes through the latter and goes through the centreaxis 34. Each opening 41 has a first longitudinal end 42 and a secondlongitudinal end 43, which opposes the first longitudinal end 42. Thelongitudinal ends 42, 43 substantially run adjacent to the contact web35. The openings 41 furthermore in each case have two mutually opposinglongitudinal sides 44, 45. The openings 41 divide the base body 39substantially into two halves. The spacing of the longitudinal sides 44,45 with respect to one another is slightly larger than the width of thearmature 3. The spacing of the longitudinal ends 42, 43 with respect toone another is slightly larger than the height of the armature 3.

Each base body 39 has an inside 46, which, when the pump is assembled,projects into the receiving space 8 and is remote from the associatedcontact web 35. Each base body 39, on the inside 46, has a contact face47, which runs parallel to the contact web 35 and forms a fixing partfor the axial fixing of the armature 3.

Two centring flanks 48, which adjoin the longitudinal side 44 or 45 ofthe respective opening 41, are also provided on each base body 39 on theinside 46 thereof The centring flanks 48 issue from the contact face 47of the respective base body 39. They run obliquely to the contact base47. A centring flank 48 is located adjacent to the first longitudinalend 42 and the second longitudinal side 45. The other centring flank 48,on the other hand, is arranged adjacent to the second longitudinal end43 and the first longitudinal side 44. The centring flanks 48 run fromthe contact face 47 in the direction of the centre axis 34. They opposeone another obliquely.

Furthermore, two opening bulges 49 adjoin each opening 41 and areprovided in the region of the centre axis 34 in the base body 39. Aspring arm, which is connected to the respective base body 39, springsinto each opening bulge 49. The spring arms 50 are arcuate. They extendin a curved manner around the centre axis 34. They can be radiallydeflected.

The opening bulges 49 are, in each case, laterally limited by innercontact flanks 87, which are provided on the base body 39 and extendadjacent to the free ends of the spring arms 50. The contact flanks 87extend parallel to one another. Each contact flank 87 borders on alongitudinal side 44 or 45 of the respective opening 41 and extends inthe base body over a thick region thereof The contact flanks 87 extendperpendicular to the contact faces 47.

The function of the pump will be described below. By providing the coils11 with current, the latter produce a magnetic field. The armature 3,which comprises the permanent magnets 16, is located in the magneticfield. The permanent magnets 16 also produce a magnetic field. Thepermanent magnets 16 and the electric drive magnets 12 together form apump body drive device or a diaphragm drive device. The armature 3 isprovided with an oscillating movement by the magnetic fields along itslongitudinal centre axis 13. In the process, it is displaced along adisplacement path. The armature 3 moves in two different directions,which, are opposed or in opposite directions to one another.

Owing to the oscillating movement of the armature 3, two diaphragms 2are actuated alternately. The centres of the diaphragms 2 arealternately pressed into the chamber parts 19 and then drawn into thereceiving space 8, so a fluid to be conveyed is conveyed.

The fluid to be conveyed is sucked via at least one panel cover into thepump housing 1 by the diaphragms 2. In the pump housing 1, the fluidflows via at least one part region along the yokes 9. It is then drawninto the suction lines 31. Via the suction openings 26, which form fluidinlets, the fluid arrives in the respective pumping chamber 4. Thefluid, in the process, passes the respective suction valve plate 28,which is then located in its release position. The pressure openings 25are, in this case, closed by the pressure valve plates 29. The fluidthen leaves the pumping chambers 4 via the pressure openings 25, whichform fluid outlets. The suction valve plates 28 prevent an unintentionalreturn of the fluid into the suction lines 31. The fluid passes therespective pressure valve plate 29, which is then in its releaseposition. It then arrives in the pressure lines 30. The fluid can thenbe removed via a collecting pressure connecting piece (not shown). Thepump can be completely housed in an outer housing.

The exchange of a diaphragm 2 will be described in more detail below. Inthis case, the operating state of the pump is assumed, which is shown inFIGS. 6 and 7. The armature 3 is not driven during the diaphragmexchange. The coils 11 are without current.

In this operating state of the pump, the armature 3 is moveable alongits displacement path. The actuating devices 32 or the fixing devices 33are in each case in their release position or non-fixing position. Theopenings 41 are oriented in such a way that the armature 3 can passthrough them. The openings 41 and the armature 3 have a common centreplane.

The actuating devices 32 are to be manually pivoted from their releaseposition about the centre axis 34 into their fixing position. Theactuating devices 32 can be pivoted simultaneously or consecutively. Theactuating handles 36, which allow a simple and reliable forcetransmission, are to be used for the manual pivoting of the actuatingdevices 32. The pivoting of the actuating devices 32 leads to acorresponding pivoting of the fixing devices 33 about the centre axis 34from their release position into their fixing position.

A centring of the armature 3 firstly takes place. This centring is shownin FIGS. 8 and 9. It takes place automatically during the displacementof the fixing devices 33 from their release position into their fixingposition. The fixing devices 33 thus also ensure a centring. The twocentring flanks 48 of a fixing device 33 come to rest synchronously onthe armature 3. The armature 3 preferably has corresponding engagementfaces 51 for the centring flanks 48. The engagement faces 51 are locatedin the region of the longitudinal ends of the armature 3 and aresubstantially perpendicular to the longitudinal centre axis 13. Arelative movement takes place between the engagement faces 51 and theassociated centring flanks 48. Because of the inclined course of thecentring flanks 48, the armature 3 is displaced from the actuatingdevice 32 which has just been actuated along the longitudinal centreaxis 13 in the direction of the other actuating device 32. By actuatingthe two actuating devices 32, a centring of the armature 3 takes placein the direction of the longitudinal centre axis 13. Each fixing device33 presses the armature 3 away from it, which leads to a centring of thearmature 3. The armature 3, after centring, is located centrally betweenthe U-legs. Furthermore, the centring flanks 48, during a centring ofthe armature 3, also act in a direction which is perpendicular to thelongitudinal centre axis 13. The armature 3 is thus also radiallycentred with respect to the longitudinal centre axis 13. The further theactuating devices 32 or the fixing devices 33 are pivoted into thefixing positions, the further the armature 3 is displaced with respectto its position.

The diaphragms 2 fastened to the armature 3 prevent a pivoting of thearmature 3 about the longitudinal centre axis 13 on actuation of thefixing devices 33. The centring flanks 48 furthermore prevent thearmature 3 from carrying out a pivoting movement about the longitudinalcentre axis 13 upon actuation of the fixing devices 33.

The fixing devices 33 then reach their fixing positions. These are shownin FIGS. 10 and 11. The contact faces 47 then rest flat on thelongitudinal ends of the armature 3 and thus secure these axially. Theopenings 41 and the armature 3 are no longer oriented one after theother or with respect to one another. The armature 3 can no longer passthrough the openings 41. The spring arms 50 prevent the fixing devices33 being able to be moved unintentionally from their fixing position.They furthermore also fix the armature 3. The spring arms 50, in thiscase, rest on the armature 3. The diaphragms 2 can then be removed fromthe armature 3. The pump heads 18 are to be removed for this purpose.

Furthermore, the contact flanks 87 of a base body 39 then rest laterallyon the armature 3 on the opposing sides of the armature 3. The contactflanks 87 of the two base bodies 39 are, in this case, spaced apart inthe axial direction along the longitudinal centre axis 13. The contactflanks 87 prevent both a rotation of the armature 3 about thelongitudinal centre axis 13 and also prevent the latter approaching thecoils 11. The contact flanks 87 therefore form fixing parts, which fixthe armature 3 transverse to its displacement path.

With a reverse actuation of the actuating devices 32, the armature 3 isreleased again.

With reference to FIGS. 12 to 19, the second embodiment of the inventionwill be described below. Identical components receive the same referencenumerals as in the first embodiment, to which reference is hereby made.Structurally different, but functionally similar components receive thesame reference numerals with an “a” thereafter. The essential differencebetween the first embodiment and the second embodiment is theconfiguration of the actuating devices 32 a and the fixing devices 33 a.The actuating devices 32 a and the fixing devices 33 a are configuredseparately here.

The pump has two actuating devices 32 a. Each actuating device 32 a hasan actuating disc 52, which is circular and is housed in the receivingspace 8. The actuating handle 36 projects radially from the actuatingdisc 52. The openings 41 axially pass through the actuating discs 52,which are point-symmetrical. Each actuating disc 52 has an outer face 37and an inner face 38. Two centring webs 53 each with a centring flank 48a project from each inner face 38. The centring webs 53 extend curved inan arcuate manner They each have uniform curvature and extend at aconstant spacing from the centre axis 34. Each centring web 53 borderson a longitudinal side 44 or 45 of an opening 41. The centring webs 53of an actuating device 32 a are, in this case, arranged obliquelyopposing one another adjacent to the longitudinal ends 42, 43. Thecentring flanks 48 a extend obliquely to the inner face 38 and to thecentre axis 34.

Furthermore provided in each actuating disc 52 are two links 54, whichissue from the inner face 38 thereof. The links 54 may be groove-like.They can, however, also completely pass through the actuating discs 52.The links 54 of an actuating device 32 a are arranged adjacent to thelongitudinal sides 44 or 45. They oppose one another obliquely. Eachlink 54 has a radially outer idling portion 55, a link pin actuatingportion 56 adjoining the idling portion 55 and a radially inner fixingportion 57 adjoining the link pin actuating portion 56. The fixingportions 57 are in each case arranged adjacent to the openings 41. Theyrun substantially straight. Their spacing from the centre axis 34 issubstantially constant. Proceeding from the fixing portions 57, thespacing in the link pin actuating portions 56 from the centre axis 34increases greatly. The idling portions 55 again have a substantiallyconstant spacing from the centre axis 34.

The pump furthermore has two fixing devices 33 a. Each fixing device 33a in turn comprises two wedge mechanisms 58. Each wedge mechanism 58 hasan outer coupling wedge 59 and an inner gripping wedge 60. A grippingwedge 60 is in each case associated with a coupling wedge 59. Thesevirtually form a wedge pair.

Each wedge mechanism 58 has a carrier 61. The carriers 61 in each casecomprise a fixing piece 68, which, when the pump is assembled, has ascrew 63 passing through it and is located adjacent to the U-base 6. Thescrews 63 are screwed into the yokes 9, so the carriers 61 are alsofixed to the yokes 9 thereby. Different securing is alternativelypossible.

Furthermore, each carrier 61 has a holder 64, which is preferablyconfigured in a rod-like manner and is connected to a fixing piece 62.The holders 64 of a fixing device 33 a run parallel to one another. Theyextend parallel to the U-legs 7 and run away from the fixing pieces 62perpendicular to the U-base 6. A coupling wedge 59 is fastened to eachholder 64. Each coupling wedge 59 has an obliquely running, free wedgeface 65, which is remote from the associated holder 64. The wedge faces65 of a fixing device 33 a face one another. A link pin 71 is providedon each coupling wedge 59 and engages in the link 54 of the adjacentactuating device 32 a.

The two holders 64 of a fixing device 33 a are connected to one anotherby two guide rods 66. The guide rods 66 extend parallel to one anotherand substantially perpendicular to the holders 64. They run parallel tothe U-base 6 and to the U-legs 7. They are fastened to the holders 64 inthe region of the mutually opposing longitudinal ends of the holders 64.The guide rods 66 extend at a spacing from the longitudinal sides of thearmature 3.

The gripping wedges 60 are displaceably guided along the guide rods 66.They have corresponding guide recesses 67 for this. Each gripping wedge60 has an obliquely running wedge face 68, which rests on the wedge face65 of an associated coupling wedge 59. Furthermore, each gripping wedge60 has a free, straight gripping face 47 a, which is arranged opposingthe wedge face 68. The wedge faces 47 a form fixing parts to fix thearmature 3. The gripping faces 47 a of a fixing device 33 a face oneanother. At least one spring element 70 is provided between the twogripping wedges 60 of a fixing device 33 a. A pressure helical spring,which forms the spring element 70, is arranged here on each guide rod66. However, instead of helical pressure springs 70, leaf springs arepreferably provided. The helical pressure springs 70 are supported onthe gripping faces 47 a of the gripping wedges 60 of a fixing device 33a. The spring elements 70, when using, for example, guiding T-grooves onthe sliding wedge faces 65 of the coupling wedges 59, can also becompletely dispensed with.

The mode of functioning of the actuating devices 32 a or the fixingdevices 33 a will be described below. In this case, the release positionof the actuating devices 32 a or the fixing devices 33 a is assumed,which is shown in FIGS. 14 and 16. The gripping faces 47 a of the wedgemechanisms 58 are spaced apart from one another there. The spacing ofthe gripping faces 47 a from one another is larger than the width of thearmature 3. The armature 3 can move along the longitudinal centre axis13. The armature 3 may pass through the openings 41.

At least one actuating device 32 a or fixing device 33 a has to beactuated to fix the armature 3. The actuating handle 36 is preferably tobe used for this. During an initial pivoting of an actuating device 32a, the centring flanks 48 a synchronously come to rest on the adjacentlongitudinal end of the armature 3, so the armature 3 is displaced alongits longitudinal centre axis 13. The armature 3 is pressed in thedirection of the other actuating device 32 a. The idling portion 55, inthis case, moves past the respective link pin 71. No forces aretransmitted between the respective link pin 71 and the links 54. Theidling portions 55 thus have no actuating function. The fixing device 33a is not yet actuated.

On a further pivoting of the actuating device 32 a, the link pinactuating portions 56 arrive at the respective link pin 71. This isshown in FIGS. 17 and 18. A force transmission takes place here betweenthe link pin actuating portions 56 and the link pins 71. In this case, arelative movement takes place between the mutually abutting wedge faces65, 68. The gripping faces 47 a therefore approach one another. Theyalso approach the armature 3, which has already been centred and is nowlocated between the gripping faces 47 a of the fixing devices 33 a. Whenguiding the gripping faces 47 a of a fixing device 33 a together, thespring elements 70 are compressed.

The final fixed position is shown in FIG. 19. The gripping faces 47 a ofa fixing device 33 a rest laterally in a planar manner on the armature 3and oppose one another. They thus secure the armature 3 locally. It isalso centred in the process. A clamping fixing is present here. The linkpins 71 are in the fixing portions 57. They are fixed there. The fixingdevices 33 a ensure a fixing of the armature 3 at two points which arespaced apart from one another along the longitudinal centre axis 13. Afront and a rear fixing virtually takes place.

With a reverse actuation of the actuating devices 32 a, the armature 3is released again in an analogous manner.

A third embodiment of the invention will be described below withreference to FIGS. 20 to 25. Identical components receive the samereference numerals as in the previous embodiments, to which reference ishereby made. Structurally different but functionally similar componentsreceive the same reference numerals with a “b” thereafter. Compared tothe two previous embodiments, the actuating devices 32 b and the fixingdevices 33 b are configured differently. The actuating devices 32 b aresimilar to the actuating devices 32 a according to the secondembodiment.

The pump has precisely one actuating device 32 b. Alternatively,however, two actuating devices 32 b may also be provided again. Theactuating device 32 b again has a circular actuating disc 52 b, which isagain point-symmetrical with respect to its centre axis 34. An actuatinghandle 36 projects radially from the actuating disc 52 b. The actuatingdisc 52 b has an opening 41 passing through it on the end face.Furthermore, two links 54 b, are provided in the actuating disc 52 b,which issue from the inner face 38 thereof The links 54 b may begroove-like. However, they may also completely pass through theactuating disc 52 b. The links 54 b extend in a curved manner around thecentre axis 34.

Each link 54 b has a link pin actuating portion 56 b and a radiallyinner fixing portion 57 b. The link pin actuating portions 56 b start inthe region of the longitudinal ends 42 or 43 of the opening 41. Theyextend according to FIG. 23 from the opening 41 clockwise and in theprocess approach the centre axis 34. The link pin actuating portions 56b, in the region adjacent to the longitudinal ends 42, 43, have a firstradius of curvature, which is larger than a second radius of curvature,which is present at the inner end of the link pin actuating portions 56b. Adjoining the inner end of the link pin actuating portions 56 b arethe fixing portions 57 b, which run straight and have substantially aconstant spacing from the centre axis 34.

The pump has two fixing devices 33 b. Each fixing device 33 b has acarrier 61 b, which is fastened by a fixing piece 62 b to the adjacentyoke 9. At least one guide rod 66 b is fastened to each fixing piece 62b. Two guide rods 66 b are provided here per fixing piece 62 b and runparallel to one another. The guide rods 66 b extend parallel to theU-legs 7 and substantially perpendicular to the U-base 6.

Two clamp-like, elongate fixing parts 47 b are displaceably guided onthe guide rods 66 b. The fixing parts 47 b are configured identically.Each fixing part 47 b has two guide recesses 67 b, which have the guiderods 66 b passing through them. The fixing parts 47 b in each case havean elongate groove-like or channel-like encompassing receiver 75. Theencompassing receivers 75 have introduction openings 72, which opposeone another.

Each encompassing receiver 75 has two longitudinal sides and twolongitudinal ends 76. Provided on each longitudinal end 76 is a centringflank 48 b, which is configured as an oblique face and axially limitsthe encompassing receiver 75. A centring flank 63, which is configuredas an oblique face and laterally limits the encompassing receiver 75, isprovided on each longitudinal side. The centring flanks 48 b oppose oneanother. The length of the encompassing receivers 75 reduces from theoutside to the inside in the region of the centring flanks 48 b. Thecentring flanks 73 oppose one another. The width of the encompassingreceivers 75 reduces from the outside to the inside in the region of thecentring flanks 73.

Furthermore, an axially projecting link pin 71 is provided on eachlongitudinal end 76 of a fixing part 47 b. When the pump is assembled,the link pins 71 engage in the links 54 b.

The mode of functioning of the pump will be described in more detailbelow. In this case, the operating position shown in FIG. 22 is assumed.The fixing parts 47 b are located there spaced apart from the armature3, so the latter is released and can move along its longitudinal centreaxis 13.

To change a diaphragm 2, the actuating device 32 b has to be pivoted byits actuating handle 36 about the centre axis 34. In this case, thelinks 54 b are also moved accordingly. A relative movement takes placebetween the links 54 b and the link pins 71. The link pins 71 move alongthe link pin actuating portions 56 b in the direction of the fixingportions 57 b. In this case, the fixing parts 47 b are actuated andmoved toward one another along the guide rods 66 b, which is broughtabout by the link coupling. In the fixing position, which is shown inFIG. 25, the fixing parts 47 b and the armature 3 are engaged. The twolongitudinal sides of the armature 3 are located in the encompassingreceivers 75. In the fixing position, the link pins 71 are locallysecured in the fixing portions 57 b. The fixing devices 33 b ensurefixing of the armature 3 at two points, which are spaced apart from oneanother along the longitudinal centre axis 13. A front and a rear fixingvirtually takes place.

When the fixing parts 47 b approach the armature 3, the centring flanks48 b bring about a centring of the armature 3 along the longitudinalcentre axis 13. Furthermore, the centring flanks 73 bring about acentring of the armature 3 transversely to its longitudinal centre axis13.

A fourth embodiment of the invention will be described below withreference to FIGS. 26 to 32. Identical components received the samereference numerals as the previous embodiments, to which reference ishereby made. Structurally different, but functionally similar componentsreceive the same reference numerals with a “c” thereafter. Compared tothe two previous embodiments, the actuating devices 32 c and the fixingdevices 33 c are configured differently.

The pump comprises two actuating devices 32 c and two fixing devices 33c. Two fixing pieces 62 c are provided here, which are fastened, whenthe pump is assembled, adjacent to the U-base 6 on the yokes 9. Twomutually parallel holders 64 c are rigidly connected to each fixingpiece 62 c and run away from the U-base 6 and in each case have abearing opening 79 at their free end. The holders 64 c extendperpendicularly to the U-base 6. The bearing openings 79 of a fixingdevice 33 c have a common bearing axis, which runs parallel to theU-base 6. A fixing part 47 c is displaceably guided parallel to theU-base 6 in each bearing opening 79. The fixing parts 47 c are in eachcase configured in a pin-like or bolt-like manner, with them preferablybeing circular in cross section. They in each case have an outeractuating end 80 and an inner fixing end 81 opposing the actuating end80. The fixing parts 47 c taper conically in the region of their fixingends 81 with the formation of centring parts 48 c. In the region of theactuating ends 80, the fixing parts 47 c in each case have a radiallyprojecting head. A helical spring 82 is arranged on each fixing part 47c. The latter in each case rests on the head of the fixing part 47 c andon the respective holder 64 c and presses the fixing part 47 c outwardlyor away from the respective holder 64 c.

The actuating devices 32 c are in each case annular. They in each casehave a radially projecting actuating handle 36. Two control cams 54 c,which are identically configured and run at the edge on the respectiveactuating device 32 c around the centre axis 34, are provided in eachactuating device 32 c. The control cams 54 c are open toward the centreaxis 34. Each control cam 54 c has a control cam beginning 84 and acontrol cam end 85. The radial spacing of the base face limiting thecontrol cams 54 c from the centre axis 34 in each decrease from thecontrol cam beginning 84 with the formation of a link pin actuatingportion 56 c in the direction of the control cam end 85. The decreasecan take place regularly or irregularly.

Fixing recesses 86 are configured in the armature 3. Provided in theregion of each longitudinal end of the armature 3 are two fixingrecesses 86, which oppose one another and have a centre axis extendingparallel to the U-base 6. The fixing recesses 86 are conicallyconfigured and are open toward the adjacent fixing parts 47 c. Thefixing recesses 86 taper from the outside to the inside.

When the pump is assembled, the heads of the fixing parts 47 c rest onthe inside of the control cams 54 c. The heads are pressed by thehelical springs 82 onto the control cams 54 c. The fixing ends 81 of thefixing parts 47 c of a fixing device 33 c face one another. The fixingparts 47 c form link pins 71 c.

The mode of functioning of the pump will be described in more detailbelow. The starting point is FIG. 30 in this case. According to FIG. 30,the armature 3 is released. The fixing ends 81 are spaced apart from thefixing recesses 86. During a pivoting of the actuating devices 32 c, theactuating ends 80 slide on the control cams 54 c. In this case, thefixing parts 47 c are pressed toward one another or in the direction ofthe armature 3 by the control cams 54 c in the link pin actuatingportions 56 c.

As emerges from FIG. 31, owing to the conical configuration of thefixing parts 47 c and the fixing recesses 86, a centring of the armature3 takes place on introduction of the fixing ends 81 in the fixingrecesses 86.

According to FIG. 32, the armature 3 is locally fixed. The fixing parts47 c and the fixing recesses 86 have a positive connection. The fixingdevices 33 c ensure a fixing of the armature 3 at two points, which arespaced apart from one another along the longitudinal centre axis 13. Afront and a rear fixing virtually takes place.

1. Pump for conveying a fluid, comprising a) a pump housing (1), b) withat least one fluid inlet (26), c) with at least one pumping chamber (4),which has a flow connection to the at least one fluid inlet (26), and d)with at least one fluid outlet (25), which has a flow connection to theat least one pumping chamber (4), e) at least one drivable pump body(2), which f) at least partially limits the at least one pumping chamber(4), g) at least one pump body drive mechanism, which has h) at leastone pump body drive mechanism (3) connected to the at least one pumpbody (2) for driving the at least one pump body (2), wherein the atleast one pump body drive mechanism (3) is movable along a displacementpath, and characterised by i) at least one actuatable fixing device (33;33 a; 33 b; 33 c) for fixing the at least one pump body drive mechanism(3), wherein the at least one fixing device (33; 33 a; 33 b; 33 c) j) ina release position, releases the at least one pump body drive mechanism(3), wherein the at least one pump body drive mechanism (3) is thenmovable along its displacement path, and k) in a fixing position, fixesthe at least one pump body drive mechanism (3) and an exchange of the atleast one pump body (2) is possible, l) can be actuated by at least oneactuating device (32; 32 a; 32 b; 32 c) which is actuably mounted on thepump housing (1), and m) comprises at least one fixing part (47, 87; 47a; 47 b; 47 c) which can be displaced by the at least one actuatingdevice (32; 32 a; 32 b; 32 c) for fixing the at least one pump bodydrive mechanism (3), being movable between the release position and thefixing position, and in its fixing position, fixes the at least one pumpbody drive mechanism (3) at least in the direction of its displacementpath.
 2. Pump for conveying a fluid, comprising a) a pump housing (1),b) with at least one fluid inlet (26), c) with at least one pumpingchamber (4), which has a flow connection to the at least one fluid inlet(26), and d) with at least one fluid outlet (25), which has a flowconnection to the at least one pumping chamber (4), e) at least onedrivable pump body (2), which f) at least partially limits the at leastone pumping chamber (4), g) at least one pump body drive mechanism,which has h) at least one pump body drive mechanism (3) connected to theat least one pump body (2) for driving the at least one pump body (2),wherein the at least one pump body drive mechanism (3) is movable alonga displacement path i) at least one actuatable fixing device (33; 33 a;33 b; 33 c) for fixing the at least one pump body drive mechanism (3),wherein the at least one fixing device (33; 33 a; 33 b; 33 c) j) whenthe pump is in an operating state, is in a release position, wherein inthe release position, the at least one pump body drive mechanism ismovable along its displacement path, and k) in a fixing position,centers the at least one pump body drive mechanism in the direction ofits displacement path, and also transversely to its displacement path,and further fixes the at least one pump body drive mechanism in thedirection of its displacement path, and in the direction transverse toits displacement path, l) wherein the at least one pump body (2) may beremoved from the at least one pump body drive mechanism with the atleast one pump body drive mechanism being maintained in the fixingposition by the at least one fixing device (33; 33 a; 33 b; 33 c). 3.Pump according to claim 2, wherein the fixing device (33; 33 a; 33 b; 33c) can be actuated by at least one actuating device (32; 32 a; 32 b; 32c), which is actuably mounted, preferably pivotably, on the pump housing(1), the at least one actuating device (32; 32 a; 32 b; 32 c) preferablycomprising at least one actuating means (36) for the actuation thereof.4. Pump according to claim 3, wherein the fixing device (33; 33 a; 33 b;33 c) comprises at least one fixing part (47, 87; 47 a; 47 b; 47 c)which can be displaced by the actuating device (32; 32 a; 32 b; 32 c)for fixing the pump body drive mechanism (3), the at least one fixingpart (47, 87; 47 a; 47 b; 47 c) being movable between the releaseposition and the fixing position.
 5. Pump according to claim 1, whereinthe fixing part (47, 47 a; 47 b; 47 c), in its fixing position, fixesthe pump body drive mechanism (3) at least in the direction of itsdisplacement path.
 6. Pump according to claim 1, wherein at least oneactuable centering part (48; 48 a; 48 b, 73; 48 c) for centering thepump body drive mechanism (3), wherein the at least one centering part(48; 48 a; 48 b, 73; 48 c) preferably has at least one centering flankfor interaction with the pump body drive mechanism (3).
 7. Pumpaccording to claim 6, wherein the centering part (48; 48 a; 48 b; 48 c)centers the pump body drive mechanism (3) in the direction of itsdisplacement path.
 8. Pump according to claim 6, wherein the centeringpart (48; 48 a; 73; 48 c) centers the pump body drive mechanism (3)transversely to its displacement path.
 9. Pump according to any one ofclaims claim 6, wherein the centering part (48; 48 a; 48 b, 73; 48 c) isconnected to the fixing device (33; 33 a; 33 b; 33 c).
 10. Pumpaccording to claim 1, wherein the fixing device (33 a) has at least onewedge mechanism (58), the at least one wedge mechanism (58) having acoupling wedge (59), which can be actuated by the actuating device (32a), and the fixing part (47 a), which interacts with the coupling wedge(59) and is configured in a wedge-like manner, at least one springelement (70) also preferably being provided to move the fixing part (47a) into its release position.
 11. Pump according to claim 1, wherein thefixing device (33 b) has at least one encompassing body (47 b) to atleast partially encompass the pump body drive mechanism (3), the atleast one encompassing body (47 b) preferably having at least oneencompassing receiver (75).
 12. Pump according to claim 1, wherein thefixing part (47 a; 47 b; 47 c) and the actuating device (32 a; 32 b; 32c) are coupled to one another by at least one link arrangement, the atleast one link arrangement having at least one link pin (71; 71 c) andat least one link (54; 54 b; 54 c) for guiding the at least one link pin(71; 71 c).
 13. Pump according to claim 12, wherein the link (54; 54 b;54 c) has at least one link pin actuating portion (56; 56 b; 56 c) foractuating the link pin (71; 71 c), the link (54; 54 b; 54 c) preferablyalso having a fixing portion (57; 57 b) for locally securing the linkpin (71; 71 c).
 14. Pump according to claim 13, wherein the link pin (71c) forms the fixing part (47 c).
 15. Pump according to claim 1, whereinthe actuating device (32) and the fixing device (33) are rigidlyconnected to one another, the fixing part (47) preferably beingconfigured as a fixing face for resting on the pump body drive mechanism(3).
 16. Pump according to claim 15, wherein the actuating device (32)comprises at least one resilient spring means (50), which, in the fixingposition of the fixing part (47), rests on the pump body drive mechanism(3) for holding the actuating device (32) in its fixing position.